In many areas of chemical research, especially pharmaceutical research, a large number of chemical compounds may be identified which exhibit chemical or biological activity in the same assay. In drug research these compounds are identified through various means including the technique of high throughput screening which has seen wide implementation in recent years. In order to understand the basis for the observed activities in order to enable the design of chemical compounds with higher activity, an understanding of the chemical substructures which are responsible for the observed activities is desirable.